1. Field of the Invention
The present invention relates to electrochemical analysis of solutions. More particularly, the present invention relates to voltametric identification of concentrations of elements in a sample solution.
2. Discussion of Background
Voltametry is a well known analytical method. Typically, a voltametric analysis, such as stripping analysis, is performed in a measurement cell having three electrodes, namely, an auxiliary electrode, a reference electrode, and a working electrode. The three electrodes are placed in a solution in the measurement cell in spaced-apart arrangement and an electric potential is then applied across the auxiliary electrode and the working electrode. As the potential difference between them is varied over a specific range, a varying current flows through the working electrode as a result of oxidation/reduction reactions of the ions in the sample solution. The voltage/current relationships measured are characteristic of the particular types of substances present in the solution and their concentrations.
The prior art discloses numerous examples of voltametric analysis applications using the conventional three-probe configuration. Banks (U.S. Pat. No. 3,428,532) and Stearn (U.S. Pat. No. 2,531,747) disclose voltametric methods of identifying metal and alloys by using the sample metal of interest as the working electrode in a conventional configuration. In U.S. Pat. No. 3,902,982, Nakagawa discloses a portable apparatus for performing voltametric analysis of city tap water. Also, Saloheimo, et al. (U.S. Pat. No. 4,786,373) disclose a voltametric method that uses the conventional three electrode arrangement with the addition of ultrasonic influences to improve analysis conditions.
Voltametric analysis methods employing nonconventional configurations is believed to be limited. Bednarski, et al. (U.S. Pat. No. 3,859,193) disclose a working electrode that also functions as a rotatable electrolysis cell to allow the analysis to be conducted much faster and with greater accuracy. In another nonconventional arrangement, Dahms (U.S. Pat. No. 3,556,950) discloses a method and apparatus for measuring a plurality of constituents in solution. The apparatus features a plurality of working electrodes, serially arranged, that are responsive to the presence of ions and dissolved gases. The multiple working electrodes are used in succession to assist in the production of voltametric analysis data.